From Field to Video Room: How Baseball’s Replay Review Will Work, by Richard Sandomir at the New York Times (2014)
Interesting how changing the rules of the game has a big impact on the technology used behind the scenes.

The system is a greatly expanded version of one that has reviewed only home run calls since August 2008. Umpires made their decisions by looking at replays on TV monitors at each stadium.

The new system links camera feeds from the 30 ballparks to the operations center. M.L.B. has also installed its own stationary high home plate cameras at each stadium to offer its video officials the best possible view of base runners who might have to be repositioned depending on their decisions.

MLB replay room

The system is starting at a time when there are fewer blustery, base-kicking, dirt-tossing managers around. How would Lou Piniella, Earl Weaver or Ozzie Guillen cope with video review?

“They’d get fired up because they didn’t have this kind of tool,” Marinak said. “Now managers have less incentive to go crazy.”